Not able to set the predefined value of the 'Type' field to 'Prospect'. Found this in salesforce docs.
To set predefined field values:
1. Click the name of an action in the Buttons, Links, and Actions list or the Global Actions list.
2. On the action detail page, click New in the Predefined Field Values list.
3. Select the field you want to predefine a value for.
4. Specify the value for the field.
5. Click Save.

Not able to found the second step. Can anyone please help me